JPH0765842A - Battery - Google Patents

Abstract

PURPOSE:To meet the recent social requirements for such as global embironmental protection, no pollution, etc., by forming a battery with compositions that are harmless and safe to human body. CONSTITUTION:An electrolyte 12 stored in a storing device 11 is composed mainly of a solution made by mixing glycol system organic matter (such as triethylene glycol, polyethylene glycol, etc.) with water, and a salt to give ion conductivity (such as lithium chloride) is added to the solution. The mixing ratio of the water contained in the electrolyte 12 is preferably 40 to 80%. Also a positive pole 13 formed with a graphite plate and a zinc plate negative pole 15 laminated on both sides of the positive pole 13 through a spacer 14 of nylon net are immersed in the electrolyte 12. A battery thus obtained plays a role for the water in the electrolyte 12 to promote electrode reaction so as to increase current, and also plays a role for the glycol organic matter to enable charging. Then it can be used as a secondary battery.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery which is pollution-free and can be reduced in price.

[0002]

2. Description of the Related Art Conventionally, as batteries, primary batteries such as manganese dry batteries and mercury batteries, and secondary batteries such as lead storage batteries, alkaline storage batteries and zinc-air storage batteries have been known.
In each of these batteries, a reduction reaction occurs on the positive electrode side and an oxidation reaction occurs on the negative electrode side during discharge.

[0003]

All of the above conventional batteries are configured to generate electric power by utilizing a chemical reaction (oxidation / reduction reaction). Therefore, the composition of the battery is harmful and harmful to human body. Containing a large amount of substances (such as cadmium, mercury, sulfuric acid, strong base, etc.), it is very troublesome to dispose of used battery waste, and the waste becomes a pollution source of the environment, causing pollution problems. It also causes the destruction of the global environment and is a serious social problem.
Moreover, since a composition having a high material cost is used, the price of the product is generally high, and there is a strong demand for lowering the price.

The present invention has been made in view of the above circumstances, and its purpose is to construct a battery with a composition that is harmless to the human body and is safe, and to meet the recent social demands of environmental protection and pollution-free. It is to provide a battery that can meet the above requirements, and can also facilitate waste treatment and reduce costs.

[0005]

In order to achieve the above object, the battery of the present invention comprises a positive electrode made of graphite or a graphite mixture, a negative electrode made of metal, and an electrolytic solution in which both positive and negative electrodes are immersed. The main component of the electrolytic solution is a solution in which water is mixed with a glycol organic material. In this case, it is preferable to add salts that give ionic conductivity to the electrolytic solution.

[0006]

The battery of the present invention is a glycol-based organic substance-
Graphite power generation element (Japanese Patent Application No. 4-201281)
Japanese Patent Application No. 4-278623, Japanese Patent Application No. 5-14326
It was born in the process of developing No. 8). The power generation element previously applied for a patent has a structure in which a metal (negative electrode) and graphite (positive electrode) are immersed in a glycol-based organic substance. This power generation element is suitable for converting thermal energy around 100 ° C. into electric energy, but since it generates electromotive force and current even at room temperature, the composition of the battery (primary battery or secondary battery) is improved. It is thought that it can also be used as.

In a conventional chemical battery, a reduction reaction occurs on the positive electrode side and an oxidation reaction occurs on the negative electrode side. On the other hand, according to the power generating element (battery), the electrode is oxidized on the negative electrode side and becomes metal ions to be eluted into the glycol-based organic substance, but electron transfer from graphite to the glycol-based organic substance occurs on the positive electrode side. (This principle is described in detail in the specification of Japanese Patent Application No. 4-201281). Holes are formed in graphite of the positive electrode due to this electron transfer, but since electrons generated on the negative electrode side flow through the external circuit to reach the positive electrode and fill the holes, the graphite of the positive electrode is apparently , I see no change. This point is greatly different from the conventional chemical battery. From the above, it is presumed that the glycol-based organic matter plays an important role not only as an electrolyte but also as an electron acceptor.

The inventors of the present invention have conducted experiments on the above-mentioned power generating element and have found that the generated power changes depending on the humidity in the air, and the generated power tends to increase as the humidity increases. Utilizing this property, we have developed a new rechargeable battery that has not been known so far.

The battery of the present invention has a structure in which a positive electrode made of graphite or a graphite mixture and a negative electrode made of metal are immersed in an electrolytic solution whose main component is a solution of a glycol organic material mixed with water. ing.

Regarding the power generation mechanism in this battery, research is still ongoing, but according to the experimental results described later, water plays a role of promoting the above-mentioned electrode reaction and generates sufficiently large power. You can Furthermore, the battery of the present invention can be used as a secondary battery because the glycol-based organic substance in the electrolytic solution plays a role of enabling charging. In this case, as will be described in detail in Examples to be described later, the electrode reaction described above can be further promoted by adding a salt that imparts ionic conductivity to the electrolytic solution.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The electrolyte solution 12 stored in the reservoir 11 contains a solution of triethylene glycol (# 150 manufactured by Mitsui Toatsu Chemical Co., Inc.), which is a glycol-based organic material, mixed with water as a main component, and this solution has ionic conductivity. For example, lithium chloride (Nacalai Tesque reagent special grade) is added at a rate of about 3 to 15 wt. The mixing ratio of water in the electrolytic solution 12 is preferably 40% to 80%.
Is.

In the electrolytic solution 12, one positive electrode 13 formed of a graphite plate and two zinc plates laminated on both side surfaces of the positive electrode 13 via spacers 14 made of nylon net are used. The negative electrode 15 is immersed. The surface of each negative electrode 15 has numerous scratches (irregularities) on its entire surface in order to increase the surface area in contact with the electrolytic solution 12.

FIG. 2 shows the performance test results of the battery constructed as described above. In the battery used in this test, the positive electrode 13 and the negative electrode 15 both had a width of 5 cm, a length of 11.5 cm, and a thickness of 0.2 mm, and the addition ratio of lithium chloride to triethylene glycol was 93: 7 by weight. Is. This triethylene glycol + lithium chloride mixed solution (570 g) was placed in the reservoir 11, and the amount of distilled water mixed with this solution was 0%, 8%, 20%, 5%.
The results of measuring the current when gradually increasing to 0% and 75% are shown in FIG. The room temperature at the time of measuring the current was around 25 ° C., and the generated voltage was about 1.2V to 1.
It was 3V. As is clear from FIG. 2, as the mixing ratio of water in the electrolytic solution 12 increases, the current also increases, and it is presumed that the water in the electrolytic solution 12 plays a role of promoting the electrode reaction. In this test result, a current of about 100 mA was obtained when the mixing ratio of water in the electrolytic solution 12 was 50%. In this test, a total of three electrodes 13 and 15 are immersed in the electrolytic solution 12, but if the number of electrodes (or surface area) is increased, the current can be increased accordingly.

This battery is rechargeable and functions as a secondary battery. For example, if a battery with a water mixing ratio of 50% is charged at a charging voltage of 5 V and 1.4 A for 10 minutes, the voltage of the battery after charging rises to 2.5 V and the current is 2 as well.
It rose to 75mA. In addition, when a mixture of water with a mixing ratio of 75% is charged at a charging voltage of 5V and 1.6A for 10 minutes, the battery voltage after charging rises to 2.4V and the current is 2
It increased to 60mA. In any case, by charging,
It has been confirmed that the battery voltage is about twice as high as before charging and the current is about 2-3 times as high as before charging.

By the way, since zinc forming the negative electrode 15 has a large ionization tendency, it is only water (100% of water).
However, a current of about 30 mA is generated. If 5% to 15% of salts such as lithium chloride is added to this water, 90 mA
Generates a current of some degree. However, it has been experimentally confirmed that these products cannot be charged because the glycol-based organic matter is not contained in the solution. Therefore, it is presumed that the glycol-based organic substance plays a role of enabling charging.

In this case, the glycol organic substance is not limited to triethylene glycol, and other glycol organic substances such as polyethylene glycol, propylene glycol and trimethylene glycol may be used.

In addition, the battery of this embodiment has the electrolytic solution 1
2 has the characteristic that the current increases when heat is applied from the outside, and when the temperature of the electrolyte solution 12 reaches about 90 ° C., the current increases more than twice as much as at normal temperature (25 ° C.). Has been done. From this, it is presumed that the battery of this example also has a thermoelectric conversion function for converting heat energy into electric energy. It has been confirmed that the temperature at which the thermoelectric conversion efficiency is high is about 90 ° C to 100 ° C.

In this embodiment, since lithium chloride is added as a salt that gives ionic conductivity to the electrolytic solution 12, the electrode reaction can be promoted and the current can be increased efficiently. However, the salts that give ionic conductivity are not limited to lithium chloride, and other metal halides such as NaCl and metal salts of inorganic acids (Na2 SO4, K3 PO4, Na).
NO3) and metal salts of perchloric acid (LiClO4, NaClO)
4) or organic acid salts such as oxalate, formate, and carboxylate. In this case, a salt having a higher solubility is more advantageous.

In this embodiment, the negative electrode 15 is made of zinc, but the present invention is not limited to this. The negative electrode 15 may be made of a metal (for example, aluminum) whose ionization tendency is equal to or larger than that of copper, It may be made of iron. Further, an activator such as manganese dioxide may be added to the electrolytic solution 12. This activator can be expected to have the effect of promoting the electrode reaction and increasing the current.

In the present embodiment, the positive electrode 13 is formed of a graphite plate, but a graphite mixture containing other components such as manganese dioxide powder may be molded into a plate shape to form the positive electrode. . Further, in the present embodiment, the nylon net is used as the spacer 14 that regulates the distance between the positive electrode 13 and the negative electrode 15, but other insulating material such as kraft paper may be used.

In addition, it goes without saying that the present invention can be implemented by variously changing the shape of the reservoir 11 and the shapes of the electrodes 13 and 15 as appropriate.

[0022]

As is apparent from the above description, the battery of the present invention is a novel rechargeable battery which has not been known so far, and is not as heavy as a lead acid battery. Moreover, since the composition of the battery of the present invention does not contain a substance harmful to the human body, it is safe and harmless to the human body, and the waste of used batteries does not become a source of environmental pollution. It is possible to meet the social demands of, and it is easy to dispose of used batteries as waste. Furthermore, the battery of the present invention has a low raw material cost of the composition, and the product price can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a battery showing an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a mixing ratio of water in an electrolytic solution and an electric current.

[Explanation of Codes] 11 ... Reservoir, 12 ... Electrolyte, 13 ... Positive electrode (graphite), 14 ... Spacer (nylon net), 15 ... Negative electrode (zinc).

Claims (2)

[Claims] 1. A positive electrode made of graphite or a graphite mixture, a negative electrode made of metal, and an electrolytic solution for immersing the positive and negative electrodes. The electrolytic solution is mainly composed of a solution of a glycol-based organic material mixed with water. A battery characterized by the following. 2. The battery according to claim 1, wherein a salt that imparts ionic conductivity is added to the electrolytic solution.